Rotatron-electrical transducer



Dec. 15, 1953 'o. G. SCHWEDE 2,662,980

ROTATRON ELECTRICAL TRANSDUCER Filed July 25, 1950 I5 Sheets-Sheet lJNVENTOR. OTTO G. SCHWED -UMTT Dec. 15, 1953 o. e. SCHWEDE ROTATRONELECTRICAL TRANSDUCER 3 Sheets-Sheet 2 Filed July 25, 1950 INVENTOR.orro a. CHM 06 Dec. 15, 1953- o. G. SCHWEDE 2,662,980

ROTATRON ELECTRICAL TRANSDUCER Filed July 25, 1950 3 Sheets-Sheet 3JNVENTOR. 070 a. CHM/50E Patented Dec. 15, 1953 (Granted under Title 35,U. S. Code (1952),

see. 266) Claims.

My invention relates to a device for controlling flow of electricalenergy.

An object of my invention is to control fiow of electrical energy bytransferring energy from an electric eddy field to a load impedance.

It is a known fact in physics that energy can be imparted toelectrically charged particles only by subjecting said particles to anelectric field. The term electric field includes two known fieldconfigurations:

(a) An electric field in which electrical charges are present and thelines of electrical force begin at a positive electrical charge and endat a negative electrical charge. This first field configuration will becalled an electrostatic field.

(Io) An electric field in which electrical charges are absent and thelines of electrical force are closed in themselves. Such a field isproduced by a varying magnetic field. This second field configurationwill be called an electric eddy field.

As there is no perfect insulator nor perfect conductor, neither a pureelectrostatic nor a pure electric eddy field can be found in electricaldevices. Therefore, an electric field is called electrostatic regardlessof the presence of a weak electric eddy field, if the movement ofcharged particles is principally determined by the electrostatic field.Similarly, if movement is controlled largely by the electric eddy field,that field determines the nomenclature used. Movement of electricallycharged particles may occurin solid, liquid and gaseous mediums, theterm gaseous medium including anything down to a vacuum of the lowestphysically attainable gas pressure.

It is known in the prior art that small particles such as electrons maybe accelerated to extremely high velocities by subjecting them to theinfluence of an electric eddy field in a gaseous medium. The high speedelectrons thus produced may be used to originate X-rays by causing theelectrons to hit a small target, thus transforming their kinetic energyinto X-rays and heat. In the design of devices embodying this knownprinciple great care is taken to compensate for centrifugal forcesexerted upon the electrons and to avoid any electrical counterforcewhich would tend to decelerate the movement of the electrons beforehitting the target, because deceleration results in decreasing emciency.

In contrast to these known devices the apparatus according to myinvention utilizes the centrifugal forces exerted upon rotating chargedparticles. My apparatus comprises an electric eddy field for whirlin theelectrons, and electrodes which maintain an electric field in oppositionto the radial movement of the charged particles to retard the movementof said particles thereby to extract electrical energy from them. Theextracted electrical energy is utilized in a load impedance connected tothese electrodes in the apparatus.

Other objects and many of the attendant advantages of this inventionwill be readily appreciated as the same'becomes better understood byreference to the following description.

Fig. l is a vertical cross-sectional view of an apparatus for control offlow of electrical energy; Fig. 2 is the horizontal cross-sectional viewtaken on line 2--2 of Fig. 1;

Figs. 3, 4, 5, and 6 show various useful modifications in accordancewith the invention;

Figs. '7 and 8 refer to oscillation generators;

Figs. 9 and 10 illustrate partial views of modifications of a cathodestructure;

Fig. 11 represents a voltage transforming device in accordance with theinvention; and

Figs. 12, 13, and 14 show combinations of a voltage converting deviceand modifications of the invention.

The drawings show the underlying principle rather than designmeasurements. Unessential parts have been omitted in order to aid in aclear understanding of the principles of the invention.

Referring particularly to Fig. 1, the underlying principle is explainedin a simple manner. The apparatus comprises an evacuated toroidalenvelope i, a cylindrical cathode 2 and a cylindrical anode 3 centrallydisposed within the envelope. The anode 3 is broken at s" to preventcirculation of induced eddy currents which would waste power needlesslyand distort the eddy field. A coil 4 connected to a source ofalternating current 5 produces an alternating magnetic field which islinked by the corefi to the envelope I. An external load impedance l isconnected across the cathode 2 and anode 3. When the coil 4 is energizedby the source 5 an electric eddy field is created within the envelope 8around the core 6. This electric eddy field induces a current in thering shaped cathode 2 thereby heating the emissive surface. Electronsare emitted from the cathode 2, are accelerated'by the electric eddyfield intermediate cathode 2 and anode 3, and start to revolve aroundthe cathode 2. At each turn the electrons gain energy from the electriceddy fieid and their velocity increases. As the electrons rotate in acircular path, centrifugal forces operate upon them sothat the path ofthe electrons becomes a spiral of ever increasing radius until theelectrons hit the anode 3. From the anode 3 the electrons travel throughthe load impedance 1 and back to the cathode 2. The flow of electronsthrough the load impedance 1 produces voltage across the terminals ofsaid load impedance and establishes an electrostatic counterfieldbetween anode 3 and cathode 2. This electrostatic counterfield acts uponsuccessive electrons which spiral around the cathode 2 in the spaceintermediate cathode 2 and anode 3. The influence of the electrostatic'ounterfield decelerates the spiralling electrons thereby extractingelectrical energy therefrom. This energy is transferred to the loadimpedance 1.- fore, the kinetic energy of the electrons when theyfinally hit the anode is less than the total energy imparted to them bythe, electric eddy field, In this way the electrons transfer energy fromthe electric eddy field tothe load impedance 1. The. direction ofrotation of the electrons around the cathode? depends upon the directionof theelectric eddy field which reverses its direction twice during eachcycle of the alternating magnet-ic field. The final efiect of the forcesoperating upon the electrons, however, is the same in both cases,namely, an electron current flows from the cathode Z to the anode 3 andproduces avolta'ge across the load impedance 1.

The function of the device, described by Fig.- 1

and the foregoing is the same as of a combination of a transformer and afull wave rectifier tube. In contrast to the latter icom'bination thedevice according to my invention does not require a secondary coil whichat high voltages must be carefully insulated, occupies a large space andhas a high weight.

A modification shown in Fig. 3 and described hereinafter comprises. inaddition to the elements of Fig. 1, rinfgshaped electrode structure 8adapted to betraversedby the electrons for shielding'the initial part ofthe movement of the electrons from the influence of i'the electrostaticcounterfield which is established between the anode 9 and the cathodel0, and a magnetic structure, ll for creating a constant magnetic fieldsubstantially normal to the effective electric eddy field. The electrodestructure 8 is connected to the c'atho de Hi and therefore has the samepotential as the cathode. l0. Its shielding effect restricts the strongelectrostatic counterfield substantially to the region between the anode9 and the electrode'structure :8. "Therefore, the electrons emitted'fromthe cathode in can spiral freely around the cathode 1'0 withinthe spacesubstantiallyenclosed by the cathode l and the rings of the electrodestructure 8. t N

Because of the centrifugal forces which operate upon the electrons, theelectrons travel the total radial distance of the ring shaped electrodestructure 8 in only a few revolutions; therefore, a constant magneticfield normal to the plane of the electrode structure8 is maintained bytwo ring-shaped permanent ma nets l disposed above and below theenvelope l3. The effective field of the magnets l I iSs'ub'stantiallyle'stficted t6 the region enclosed by the cathode 10 andthe electrae structure 8. QThis' constant magnetic field counteracts thecentrifugal forces with the result that the electrons spiral around thecathode II! in a large number of turnsuntil they enter the electrostaticcounterfield. Because of the many turnsthe velocity of the electronswill be high enough toen'gen'der a centrifugal force sufficient toovercome'the repelling forces of the electrostatic counterfield.

There? Another modification described hereinafter and shown in Fig. 4comprises a coil i lin place of the permanent magnet ii shown in Fig. 3.The coil is energized by a source of direct current ['5 and produces aconstant magnetic field substantially coinciding with the electric eddyfield. This magnetic field prevents the electrons from deviating out ofthe plane of the electric eddy field. Therefore, the effect of strayfields at the outer edge of the electrode structure I! and of repellingforces within the electron stream which tend to drive the electronstoward the electrode structure I! is minimized and the electrons rotatewithin the region enclosed by the cathode I8 and the electrode structureI! until they have reached a s'ufliciently high velocity which isaccompanied by such centrifugal force as to enable the electrons toovercome the repelling forces of the electrostatic counterfield.

A further improvement upon the embodiments shown'in Figs. 1,2, '3, and 4results from the arrangement shown in Fig. 5, where an additionalelectrode structure [9 is provided. This electrode structure [9, in thenature of a grid adapted to be traversed by the'e'mitted electrons, isdisposed intermediate the cathode 2i and the anode 22 and is connectedto a source of alternating voltage 23. By means of this electrodestructure IS the now of electrons may be additionally controlled at theinitial part of the spiral movement of the electrons where thecentrifugal forces are low Thus the amplitude of the control voltage 23maybe small. The load impedance 24 comprises a resistor 25 and acapacitor 21.

In the modification shown in Fig. 6 a radial shield 29 has been addedwithin the anode 28 to retard the circumferential movement of theelectrons, and an external impedance 3! employed to connect the twomembers. Fig. 6 also illustrates an alternative way of constructing thering shaped electrode '34 by insulating it from the cathode iii Withinthe envelope, and connecting 3B and 34 externally thru an impedance 32.As in the other embodiments, the load 35 is connected between anode 28and cathode 36. An impedance 33 maybe connected between electrode 34 andanode23, the two impedances 32 and 33 thus forming a fixed potentiometerfor determining the potential of theelectrode 34. Like the anode,

the electrode 3 is broken at 36 to block circulation of eddy currents.

Another modification of an anode structure is shown in Fig. 7 where theanode structure comprises two semi-cylindrical halves 37 and 3& whichare connected to the two opposite terminals of a tuned circuit 39serving as a load impedance. The electrons revolving around the cathodeclose to the anode structure 3? and 38'pass the gaps Gil between 37 and38 thereby inducing electrical currents which may be utilized tomaintain oscillation of the tuned circuit 3Q. Anadditionallcad'impedance is connected between the cathode 41 and asuitable point of the tuned circuit'39. Its purpose is to provide asource of voltage between the anode structure 3138 and the cathode ll byutilizing the voltage drop which is established across a load impedanceby a current flowing through that load impedance. The effectof theelectrostatic field maintained by that voltage between the anode and thecathode upon the rotating electrons causes them to rotate many timesclose to theanode before impinging upon the anode.

:A further modification of an "anode structure exhibiting certainadvantages for generation 'of microwaves is shown in Fig. 8. In theanode structure d2 whi h substantially encloses an orbital space arecavities id serving as load impedances and having the properties oftuned resonant circuits with openings 33 toward the orbital space Asource of voltage ill is conected to the an 'tructure s2 and the cathodet3. As described in the foregoing the electrostatic field establishedthat source of voltage 4? between the anode 4-2 and the cathode istogether with the electric eddy field from the iiux path c; causes theelectrons to rotate many times close to the anode l? before impingingupon it. During these rotations part of the electrons are retarded intheir tangential movement by the field across the openings 5% of thetuned cavities ll-'2 whereby energy is transferred into the tunedcavities. These electrons are forced slightly back towards the cathodeby the electrostatic eounterfield between anode and cathode and rotatein an orbit smaller radius. Then by the effect the electric field, theyare accelerated to of their former velocity, rotat again in their formerorbit close to the anode and transfer the accumulated energy to thetuned cavities id. The other part of the electrons are accelerated intheir tangential movement by the field across the openings 26 of thetuned cavities whereby energy is transferred from the tuned cavities tothe electrons. These electrons increase the radius of their orbitbecause the higher velocity is accompanied by a higher centrifugalforce. These electrons will quickly impinge upon the anode 62. Theresult of the described mechanism is excess of electrons which arecapable of transferring energy from the electric eddy field into theload impedance represente by the tuned cavities 55.

Further features of my invention consist in providing a cathode 55, thegeometrical shape and disposition of the emissive surfaces of thecathode being such as to establish angles greater than zero between theplane of the surfaces and the lines of force or" the alternating eddyfield as shown in 9, wherein 5g is a magnetic core, 55 is a cathode, 52are emissive surfaces of the cathode and 53 are lines of force of theelectric eddy field. As can be seen the emission of the cathode dependsupon the rotational direction of the eddy field. Clockwise rotation, asindicated by solid arrows, results in increased emission because theelectrons are accelerated away from the cathode by the el ctric eddyfield and start a spiral path which removes them from the surfacesCounter-clockwise rotation, as indicated by dotted arrows, repelselectrons already having leit the cathode 5i baol: towards the cathoderesulting in a decreased emission. Changing the disposition of theemissive surfaces, of course, will reverse the efifect. Therefore, it ispossible to design cathodes responding to clockwise and cathodesresponding to counterclockwise rotations of the electric eddy field.These cathodes, as distinguished from bidirectional cathodes whichrespond to either rotation of the elec "ic eddy field, will be referredto hereinafter as left and right directional cathodes.

Another modification of a rotation sensing cathode structure is shown inFig. 1c, wherein an is a magnetic core, is a hi-clirectionalcathode asdefined in the foregoing, 55 are electrode structures di posed in thepath of the emitted electrons such that electrons spiraling clockwisecan traverse these electrode structures 55, while electrons spiralingcounterclockwise will impinge upon these electrode structures 56; Theelectrode structures 55 are electrically connected to the cathode 54 sothat the electrons upon impinging thereon may return to the cathode 54.

Combinations of features described in the foregoing are shownschematically in Fig. 11, where is an envelope, li is a coil connectedto a source of alternating current 52 thereby producing a periodicallyalternating magnetic field which is linked by a magnetic core 62' to theenvelope 5'! and to electrode structures 58, 59, El, and 62. 58 is aright directional and iii a left directional cathode as defined above.59 and 62 are anodes surrounding the cathodes. Cathode 5B of the upperstructure is electrically connected to anode of the lower structure andto one terminal of a load impedance 63. Cathode 6! of the lowerstructure is electrically connected to anode 59 of the upper structureand to the other terminal of the load impedance 63. When the coil 51 isenergized, the current flowing through the load impedance 83 is analternating current. The voltage across the load impedance 63 may be ashigh as several thousand volts or as low as a fraction of a voltdepending upon the design.

Another useful combination is shown in Fig. 12. It comprises a structurewhich converts D. C. voltage into a periodically varying current therebyproducing a periodically varying magnetic field which is linked tostructures connected to load impedances. The converter structurecomprises an envelope E54, a left and right directional cathode (i5 and6? connected together, two anodes and E59, connections between theanodes and the corresponding terminals of two coils ii and 52, a lowvoltage battery 13 the negative terminal of which is connected to thecathodes at and 5'5, the positive terminal to the other terminals of thetwo coils H and 12. The magnetic field of the two coils is linked by thecore 57 to the envelope 64 and the electrode structures therein. Becauseof the direction sensing properties of the cathodes 66 and 67 anincreasing current in coil ii increases the current from cathode $6 toanode 68 and suppresses any current from cathode ii? to anode 69. Thecurrent in coil ll increases until it has reached its peak value and themagnetic field produced by it will be constant resulting in a decreasingcurrent from cathode 66 to anode 88. This decreasing current inconsequence reverses the direction of the electric eddy field resultingin a current from cathode d"? to anode 59 and suppression of the currentfrom 65 to 5B. In the next half cycle, coil 12 is energizedand coil H isde-energized. The circuit described in the foregoing, therefore,performs like a switch or chopper Without moving parts. The magneticfield produced by the coils H and i2 is a periodically varying field andmay be linked by the same core 67' to another coil is which is connectedto a load impedance i6. Consequently the current through this loadimpedance is an A. C. current. Core 67' may also link the periodicallyvarying magnetic flux to a structure comprising an envelope ill, abi-directional cathode l8 and an anode 19 therein, and connectionsbetween this anode and cathode to a load impedance 8!. The mode ofoperation of this latter structure is the same as that described for 1.The current through the load impedance 8! is substantially a D. C.current.

In Fig. 13 multiple combinations-0f apparatus according to my inventionare presented schematically. The converter structure is described in theforegoing example and illustrated by Fig.

12 where like numbers su'fiixed with a denote sesame Highyo1t'ag'e"enei'g'$ "for "powering theoscinb scope "94" niaTbe'conveniently obtained "from' a'," high" voltagegenerating"means Fig; 3;also li'rik'edto' the'eqre sr-frfom whichiti'obtai'ns its basic energy;I This ifig'h direct Voltage i's'abjolied through a filter' 'flb tothosc'illoscope.

A source of alternating Voltage power sci-"m ciden'tal uses such as the'heating 0f'is'o1ated cathodes'm'ay 'beobtiainefbyI winding aco'il' 96around'th eo'reeli From '-the above description; it will- V beseen"that' 'in a single apparatus -a-gre at' many -0f the concepts containedwithin appl-icant 1 invention may-be conveniently-embodied." Y

It is nndevstood -that the; inventiom is --not-- re-- stvictedio--the-'}1se-=of-e1ectrons-as-charged particlesz A-usefu1-improvement consistsin pro s d'iiei'fig al-ti 'th cathode both iosi'tivly" ans atikiel'ychargedear fiie esg thereby utilizing the co'rfi'tieflsating andsh'ielding' effect" of particles" of oiifgo'site signs. V

If desired; the enema-ting eddy fie1d rn'elj' produced b3 en'iploy'iriga sourceof const'a'nt and then varying the magnetic proper} ties"- ofthe InagnetiC structure-B; or by mechanicall? displacing a magneticstructure. 7

A further user-n1- niddification' of my invention consists inadditionally providing an electrode" strii'ctuie adapte'd'td btraversedby thej'charg'ed" particle's-travellingbetween the cathode ahdthe anode to maintain a missingelectric eld;

Obvi'o'uljrh'ein'y modifications} and variations of- -th'e' presentinvention arepdssime' in *thelight ofthe above" teachings It istherefore to" be" understood that within the scope of the" at) pendedclaims the invention may Be practice-(r otherwisethan -a's'-s11ecifica11y* qscnb'ea;

The iiiv'ention describedherein may be rna'nu factnred andf' 1155:1 53or for the' overnment of the United States of America for gavel nnientaipursds'es With'on-t" the ayment of any royaltiesthereon 0'1 therefor!Whatis claifne d is z' 1. Apparatus for cbmromrig tHe-fiovsf o'f'- electricalenergy conibrisin'gan efiv'eo'p'e, a plurality ofspaced-electrode" striictilre's" therein incliidin a source of' chargedparticles and an; anode} means m creame an electric eddifildintermediate said son-roe and said anode; means for preventing saidfirst nien't ibneofmea-n s from ere ati'ng amagnetic-field intermediatesaidso'urb" and anode, and-"a; 10wimpeda ce-Camden 'be-i-itweenicornponent'si of said electrodestriitiii s" siich thatanelectrirf-c'oiiziterfiehl' is created "j termediate said source andanode to decelieirate' said pa-rti'c1es';'- and therebieX-"ti'a'ctelectrical .rneans'forpreventing" said varying" fitgiffrornfol? lowing a path nc ud ngthe sp ce-intermediate said source and.anode, and a load impedance 0011i" neeted between" components" of saidelectrode structure such that an electricconnterfield is'cref atedintermediatesaid'soiirce'and anode'whe'feby eleetri'cal'en'e'rgydsextracted from saidabiia said device? 4. Apparatus as defined in claim 2including means for creating a constant magnetic field intermediate saidsource and anode, said magnetic field being substantially normal to saidelectric eddy field.

5. Apparatus as defined in claim 3 including an electrode structureadapted to be traversed by said particles, for shielding part of themovement of said particles from the influence of said electriccounterfield.

6. Apparatus as defined in claim 1 including an electrode structureintermediate said source and anode adapted to be traversed by saidparticles and connections from said structure and said source of chargedparticles to a source of voltage for additionally controlling the dew ofsaid particles through said structure.

'7. Apparatus for controlling the fiow of electrical energy comprising atoroidal envelope, a cathode and an anode disposed therein, a coiladapted to establish a periodically varying magnetic flux, therebyproducing an alternatin electric eddy field which reverses its directiontwice during each cycle of said magnetic flux, a magnetic structurelinking said varying magnetic fiux to said envelope, said structureincluding means for preventing said varying fiux from creating amagnetic field intermediate said cathode and anode, said cathode havingthe property of emitting only during one direction of said alternatingeddy field, and a load impedance connected to said cathode and anodesuch that an electric counterfield is created therebetween, wherebyelectric energy is extracted from said apparatus.

8. Apparatus for controlling th flow of electrical energy comprising atoroidal envelope, a cathode and an anode disposed therein, a coiladapted to establish a periodically varying magnetic flux, a source ofvoltage, a magnetic structure linking said varying magnetic fiux to saidenvelope, said structure including means for preventing said varyingmagnetic fiux from creating a magnetic field intermediate said cathodeand anode, connections from said anode to one terminal of said coil andfrom said cathode to one terminal of said source of voltage, connectionsfrom the other terminal of said coil to the other terminal of saidsource of voltage, whereby the foregoin cooperate to produce analternating electric eddy field, which reverses its direction twiceduring each cycle of said magnetic fiux, said cathode having theproperty of emitting only during one of said directions of saidalternating eddy field, and comprising in addition a second cathode andanode suitably disposed with respect to said varying magnetic flux, 2.load impedance and connections from the terminals of said load impedanceto said last cathode and anode such that an electric counterfield iscreated intermediate said last cathode and anode whereby electricalenergy is extracted from said apparatus.

9. Apparatus for controlling the flow of electrical energy comprising atoroidal envelope, two separated electrode structures disposed therein,each of said structures comprising a cathode and it an anode, two coilsadapted to establish a pcriodically varying magnetic flux therebyproducing an alternating electric eddy field which reverses itsdirection twice during each cycle of said magnetic flux, a third coil, aload impedance, a magnetic structure linking said varying netic flux tosaid envelope and to said third coil, said structure including means forpreventing said varying magnetic fiux from creating a magnetic fieldintermediate said cathode and anode, a source of voltage, connectionsfrom said two cathodes to one terminal of said source or" voltage,connections from each of said anodes to cor responding terminals of saidtwo field coils such that an electric counter-field is createdintermediate said cathodes and anodes, connections from the otherterminals of said field coils to the other terminal of said source ofvoltage, said cathodes having the property or" alternatingly emitting inaccordance with the alternating direction of said alternating electriceddy field, and connections from said third coil to said load impedancewhereby electric energy is extracted from said apparatus.

'10. Apparatus for controlling the flow of electrical energy whichcomprises a toroidal envelope, two separated electrode structuresdisposed therein, said structures comprising a first cathode and anodeand a second cathode and anode, a coil adapted to establish aperiodically varying magnetic flux thereby to produce an alternatingelectric eddy field which reverses its direction twice during each cycleof said magnetic flux, a magnetic structure linking said magnetic fluxto said envelope, said structure including means for preventing saidvarying magnetic fiux from creating a magnetic field intermediate saidcathode and anode, a load impedance, connections from said first cathodeto said second anode and to said load impedance, and connections fromsaid first anode to said second cathode and to the other terminal ofsaid load impedance, whereby an electric counterfield is created betweensaid cathodes and said anodes thereby ex tracting electrical energy fromsaid apparatus, said first cathode having the property of emitting onlyduring one of said directions of said electric eddy field, said secondcathode having the property of emitting only during the other of saiddirections of said eddy field.

OTTO G. SCI-IWEDE.

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